{Reference Type}: Journal Article {Title}: Ras-PI3K pathway promotes osteosarcoma progression via regulating VRK1-mediated H2A phosphorylation at threonine 120. {Author}: Xu X;Yu H; {Journal}: Artif Cells Nanomed Biotechnol {Volume}: 47 {Issue}: 1 {Year}: Dec 2019 {Factor}: 6.355 {DOI}: 10.1080/21691401.2019.1687506 {Abstract}: Background: Ras-PI3K pathway aberrant activation plays an important role in the occurrence and development of osteosarcoma. This study investigated the functions of Ras-PI3K pathway specific activation on histone H2A phosphorylation at threonine 120 (H2AT120ph) in osteosarcoma cells, along with the possible internal molecular mechanisms.Methods: Cell transfection was done to alter RasG12V/Y40C, H2AT120ph and vaccinia-related kinase 1 (VRK1) expression. Then, cell viability, proliferation, migration and cell cycle distribution were assessed, respectively. qRT-PCR was utilized to measure the VRK1 and Ras-PI3K pathway downstream genes (CYR61, IGFBP3, WNT16B, NT5E, GDF15 and CARD16) expression. Chromatin immunoprecipitation (ChIP) was conducted to evaluate the input levels of H2AT120ph and VRK1 in the promoter regions of Ras-PI3K pathway downstream genes.Results: Ras-PI3K specific activation promoted histone H2AT120ph. H2AT120ph participated in the oncogenic functions of Ras-PI3K pathway on osteosarcoma by modulating the transcription of Ras-PI3K-targeted genes. Moreover, VRK1 contributed to the Ras-PI3K specific activation-induced up-regulation of H2AT120ph and osteosarcoma progression. Ras-PI3K pathway-specific activation-induced up-regulation of H2AT120ph was achieved by up-regulation of VRK1.Conclusions: Ras-PI3K pathway activation promoted osteosarcoma progression might be via up-regulating VRK1-mediated H2AT120ph. We proposed that VRK1 and H2AT120ph could be the potential targets for osteosarcoma diagnosis and treatment.HighlightsH2AT120ph is specifically promoted by Ras-PI3K pathway activation.H2AT120ph joins in the oncogenic effects of Ras-PI3K pathway on osteosarcoma.H2AT120ph regulates the transcription of Ras-PI3K-targeted genes.VRK1 takes part in the regulatory function of Ras-PI3K pathway on H2AT120ph.